1. Field of the Invention
The present invention relates to an evaporation apparatus and a thin film forming method using the same, and more particularly, to an evaporation apparatus and a thin film forming method using the same which can increase a thickness uniformity of a thin film even when a target object is large.
2. Description of the Related Art
In a flat panel display such as an organic light emitting display (OLED), an organic material or a metal used for an electrode is formed as thin films on a flat panel by evaporating a corresponding material in a vacuum atmosphere.
In such a thin film formation, a thickness uniformity of the thin film greatly affects the features of the flat panel display, such as effective dispersion and color coordinate dispersion. Thus, research has been conducted in order to increase the thickness uniformity of thin films when evaporation is performed.
For example, according to an evaporation apparatus disclosed in Korean Patent Laid-Open Publication No. 2004-0007811, entitled “A vacuum evaporation apparatus and design method of shield member for the vacuum evaporation apparatus”, the evaporation apparatus includes a shield member for making the thickness of the thin film uniform and which is located between a substrate and an evaporation source heating and evaporating an evaporation material. However, the disclosed evaporation apparatus is intended for small substrates, and thus, it is difficult to apply the disclosed evaporation apparatus to large substrates.
Japanese Patent Laid-Open Publication No. 2004-238663, entitled “Evaporation apparatus” discloses an evaporation apparatus which attempts to efficiently control a dispersion angle of an evaporation material and to optimize a film thickness distribution. This evaporation apparatus can easily perform evaporation in a large-area substrate by using a linear evaporation source, and includes a shielding element in the linear evaporation source, wherein the shielding element is for shielding the evaporation material. However, this particular evaporation apparatus can only be applied to a fixed evaporation source and has to match a size of a substrate.